# AWS Athena optimization | Cloud Efficiency Hub Canonical: https://www.pointfive.co/efficiency-hub/cloud-services/aws-athena 2 documented AWS Athena cost inefficiencies, each with how to detect it and how to fix it. [Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) 2 documented AWS Athena cost inefficiencies, each with how to detect it and how to fix it. ## 2 inefficiencies [All services](https://www.pointfive.co/efficiency-hub#browse-by-service) - AWS Athena CER-0136 ### [Unmanaged Growth of Athena Query Output Buckets](https://www.pointfive.co/efficiency-hub/inefficiencies/unmanaged-growth-of-athena-query-output-buckets) When a workgroup writes results to a customer-managed S3 location, Athena generates a new S3 object for every query result, regardless of whether the output is needed long term. Over time, this leads to uncontrolled growth of the output... Storage - AWS Athena CER-0188 ### [Inefficient File Format and Layout for Athena Queries](https://www.pointfive.co/efficiency-hub/inefficiencies/inefficient-file-format-and-layout-for-athena-queries) Storing raw JSON or CSV files in S3 - especially when written frequently in small batches-leads to excessive scan costs in Athena. These formats are row-based and verbose, requiring Athena to scan and parse the full content even when only... Compute ## More AWS services - [AWS EC2 23](https://www.pointfive.co/efficiency-hub/cloud-services/aws-ec2) - [AWS RDS 19](https://www.pointfive.co/efficiency-hub/cloud-services/aws-rds) - [AWS S3 15](https://www.pointfive.co/efficiency-hub/cloud-services/aws-s3) - [AWS Lambda 12](https://www.pointfive.co/efficiency-hub/cloud-services/aws-lambda) - [AWS EBS 10](https://www.pointfive.co/efficiency-hub/cloud-services/aws-ebs) - [AWS CloudWatch 8](https://www.pointfive.co/efficiency-hub/cloud-services/aws-cloudwatch) - [AWS EKS 8](https://www.pointfive.co/efficiency-hub/cloud-services/aws-eks) - [AWS ElastiCache 8](https://www.pointfive.co/efficiency-hub/cloud-services/aws-elasticache) - [AWS DynamoDB 7](https://www.pointfive.co/efficiency-hub/cloud-services/aws-dynamodb) - [AWS Bedrock 6](https://www.pointfive.co/efficiency-hub/cloud-services/aws-bedrock) --- Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.